updated sync with info_grid

collections/farmers/farming_optimization/farming_optimization.md

@@ -6,6 +6,7 @@ The section [Build a 3Node](3node_building.md) covered the notions necessary to
 
 - [GPU Farming](gpu_farming.md)
 - [Set Additional Fees](set_additional_fees.md)
+- [HDD-Only Nodes](hdd_only_nodes.ms)
 - [Minting Receipts](minting_receipts.md)
 - [Minting Periods](minting_periods.md)
 - [Room Parameters](farm_room_parameters.md)

collections/farmers/farming_optimization/hdd_only_nodes.md

@@ -0,0 +1,37 @@
+<h1> HDD-Only Nodes</h1>
+
+<h2> Table of Contents </h2>
+
+- [Introduction](#introduction)
+- [Requirements](#requirements)
+- [BIOS Parameters](#bios-parameters)
+- [Bootstrap Image for HDD-Only Nodes](#bootstrap-image-for-hdd-only-nodes)
+
+---
+
+## Introduction
+
+It is possible to create an HDD-only node. This means that this node doesn't have SSD disks, but only HDD disks.
+
+The steps are almost all the same, except for the creation of the Zero-OS Bootstrap image, which needs an extra kernel argument.
+
+The requirements and BIOS parameters differences are also covered.
+
+## Requirements
+
+An HDD-only node needs at least 100GB of HDD disk.
+
+## BIOS Parameters
+
+In the BIOS, make sure to set `AHCI` for SATA disks.
+
+## Bootstrap Image for HDD-Only Nodes
+
+To create an HDD-only node, the bootstrap image needs an extra kernel argument:
+
+- Navigate to the [Zero-OS Bootstrap site](https://bootstrap.grid.tf/).
+- Select `Expert mode` from the menu at the top.
+- Fill in all the needed inputs (Farm ID, network, kernel and format).
+  - You can keep the default kernel
+- In the `Extra kernel arguments` input field, type `missing-ssd`.
+- Generate and download the image.